class_docstr: A Mixin for applications that start InteractiveShell instances.
  
  Provides configurables for loading extensions and executing files
  as part of configuring a Shell environment.
  
  The following methods should be called by the :meth:`initialize` method
  of the subclass:
  
    - :meth:`init_path`
    - :meth:`init_shell` (to be implemented by the subclass)
    - :meth:`init_gui_pylab`
    - :meth:`init_extensions`
    - :meth:`init_code`
docstr: Load all IPython extensions in IPythonApp.extensions.
  
  This uses the :meth:`ExtensionManager.load_extensions` to load all
  the extensions listed in ``self.extensions``.
docstr_tok: ["Load","all","IPython","extensions","in","IPythonApp.extensions",".","This","uses","the",":","meth",":","`","ExtensionManager.load_extensions","`","to","load","all","the","extensions","listed","in","``","self.extensions","``","."]
code: def init_extensions(self):
      """Load all IPython extensions in IPythonApp.extensions.
  
      This uses the :meth:`ExtensionManager.load_extensions` to load all
      the extensions listed in ``self.extensions``.
      """
      try:
          self.log.debug("Loading IPython extensions...")
          extensions = self.default_extensions + self.extensions
          if self.extra_extension:
              extensions.append(self.extra_extension)
          for ext in extensions:
              try:
                  self.log.info("Loading IPython extension: %s" % ext)
                  self.shell.extension_manager.load_extension(ext)
              except:
                  if self.reraise_ipython_extension_failures:
                      raise
                  msg = (
                      "Error in loading extension: {ext}\n"
                      "Check your config files in {location}".format(
                          ext=ext, location=self.profile_dir.location
                      )
                  )
                  self.log.warning(msg, exc_info=True)
      except:
          if self.reraise_ipython_extension_failures:
              raise
          self.log.warning(
              "Unknown error in loading extensions:", exc_info=True
          )
  
imports: from __future__ import absolute_import
  from __future__ import print_function
  import glob
  from itertools import chain
  import os
  import sys
  from traitlets.config.application import boolean_flag
  from traitlets.config.configurable import Configurable
  from traitlets.config.loader import Config
  from IPython.core.application import SYSTEM_CONFIG_DIRS, ENV_CONFIG_DIRS
  from IPython.core import pylabtools
  from IPython.utils import py3compat
  from IPython.utils.contexts import preserve_keys
  from IPython.utils.path import filefind
  from traitlets import Unicode, Instance, List, Bool, CaselessStrEnum, observe
  from IPython.terminal import pt_inputhooks
label_desc: Use image node_id 5 for calling the InteractiveShellApp obj's underlying member method code with example usage: obj.init_extensions() without return types